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Is CFM at X fan speed a linear function?

Sujalama
By Sujalama
in Cooling
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I have the Corsair Crystal Series 570X  case with 3 SP120 RGB in the front and two SP120 RGB at the top.
The case clearly was designed for having all fans as intake but I want the 2 fans in the top to have the LEDs facing the inside of the PC which requires me to configure them as intake.

I have the h100i GTX at the top and my 980Ti Hybrids Radiator in the front.
Let's say I configure my two top exhaust fans (through Grid+ V2) to run at 70% speed. Would 3 fans at 50% then cause a positive pressure?
If you know what I mean. *redneck accent* Don't want them dusts to settle in my case

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Depends on the CFM of each fan. It isn't as simple as "3*.5 and 2*-0.7=0.1". You need to know the CFM at each step and then determine what wattage or % speed you'll need to produce the desired effect.

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No, the case wasn't designed to use all intake fans.

The restrictions of the case/rads already vary and will limit the airflow of each fan in different ways. The sweet spot where airflow will be linear with rpm will depend on a combination of the fan design and where the fan is being used.

It's complicated. It'll take testing to figure out what works in your case.

If you ever need help with a build, read the following before posting: http://linustechtips.com/main/topic/3061-build-plan-thread-recommendations-please-read-before-posting/
Also, make sure to quote a post or tag a member when replying or else they won't get a notification that you replied to them.

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